This invention relates to connectors for connecting structural members, in particular the connecting wooden beams together at various angles with the connectors hidden.
Many methods exist for connecting wooden structure elements together both at angles an one positioned over the other. Such methods include nails, bolts, screws, and the like.
A variety of shaped sheet metal brackets are available, such as those manufactured and distributed by Simpson Strong-Tie CO., Inc., etc. These brackets are generally formed from heavy gage galvanized sheet metal and have a hanger surrounding an end of one wooden member such as a joist or beam and a flange portion engaging the other member such as a post or stud. The hanger and flange are fastened to the wood with nails.
These devices are successful for holding wooden structural members together. However these connectors may allow relative movement of the members during earthquakes, tornadoes, other severe storms and the like, severely weakening the connection, since forces applied to a connection can easily loosen nailed fasteners. In order to accommodate connections made at different angles, with wooded members having different dimensions a wide variety of different brackets must be made and kept in inventory. When used in outdoor applications, the exposed brackets are subject to unsightly rusting which can cause staining the adjacent wood. Also, these connectors are not attractive when exposed to view in the completed structure, such as with exposed ceiling beams.
In some wood joining applications, such as door frames, window frames and shutters, the joints are usually held together by glue which can easily crack and separate when stressed or jolted. Separation of the joint weakens the structure and is unsightly. Further, glue joints cannot be easily disassembled for maintenance such as replacement of a defective or damaged part.
Thus, there is a continuing need for improved connector systems for wooden structures that improved resistance to connector movement, provide high strength and provide an attractive appearance.
The above-noted problems, and others, are overcome by the connector system of this invention which basically comprises a kit for each connection that includes at least one cylindrical component having two spaced holes in an end of the cylinder and two transverse holes through the side of the cylinder. The end holes are parallel to the cylinder axis and the transverse apertures are preferably perpendicular to the cylinder axis. At least some of the holes are threaded. The kit further includes bolts sized to thread into threaded holes and pins sized to slide into the threaded or unthreaded holes.
While not all of the holes need to be threaded, as detailed in the description below of several embodiments of this invention, if desired for greatest versatility and to use the smallest number of different cylinders, all of the holes could be threaded and could receive either bolts or pins as desired.
If desired, holes may have two different diameters, a narrow portion for receiving the threaded portion of a bolt or the like and a wider, countersunk, portion to receive the bolt head below the surface of the cylinder.